// 断点定义
$breakpoints: (
  'mobile': 768px,
  'tablet': 1024px,
  'desktop': 1200px,
  'wide': 1440px
);

// 响应式混入
@mixin respond-to($breakpoint) {
  @if map-has-key($breakpoints, $breakpoint) {
    @media (min-width: map-get($breakpoints, $breakpoint)) {
      @content;
    }
  }
}

@mixin respond-below($breakpoint) {
  @if map-has-key($breakpoints, $breakpoint) {
    @media (max-width: map-get($breakpoints, $breakpoint) - 1px) {
      @content;
    }
  }
}
